Effects of a new titanium fluoride derivative on enamel de- and remineralization

Distribution of elements in teeth and inhibition of demineralization by titanium fluoride: Effects of concentration and pH in a titanium fluoride solution

The purpose of this study was to assess the effects of titanium fluoride (TiF₄) concentration and pH on fluoride distribution and demineralization of root dentin surfaces. Concentrations of 0.1%, 1%, and 2% TiF₄ (pH 1), 1% TiF₄ solution adjusted to pH 4, 5, 6, and 1.35% sodium fluoride (NaF) solution were applied to root dentin surfaces. Each specimen was subjected to pH cycling (pH: 4.5-7.0) for 4 weeks. Lesion depth and calcium, fluorine, and titanium distribution were then evaluated. Our limited study indicates that lesion depth and fluorine and titanium distribution in dentin depend on the concentration of a TiF₄ solution. We also found that a 1% TiF₄ solution adjusted to a pH 4-6 can reduce demineralization as effectively as a similar concentration of NaF.

Characterization and effect of nanocomplexed fluoride solutions on the inhibition of enamel demineralization created by a multispecies cariogenic biofilm model

OBJECTIVES

The aim of this study was to assess the in vitro caries preventive effect of nanocomplexed solutions of hydroxypropyl-β-cyclodextrin and γ-cyclodextrin associated with titanium tetrafluoride (TiF₄) after different complexation times (12 or 72 h).

MATERIALS AND METHODS

Enamel blocks were randomly distributed in 9 groups (n = 11): negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, TiF₄, hydroxypropyl-β-cyclodextrin:TiF₄ 12 h, hydroxypropyl-β-cyclodextrin:TiF₄ 72 h, γ-cyclodextrin:TiF₄ 12 h, γ-cyclodextrin:TiF₄ 72 h, and NaF (positive control). The solutions were applied for 1 min and the blocks were exposed to a biofilm model. Nanocompounds were characterized by differential scanning calorimetry and X-ray powder diffraction. The percentage of surface microhardness loss (%SML), mineral density changes (ΔZ), lesion depth, surface morphology (scanning electron microscopy-SEM), and chemical characterization (energy-dispersive spectroscopy-EDS) were assessed.

RESULTS

No oxidation was observed, and the formation of the nanocomplexes was evidenced by changes in the melting point compared to pure cyclodextrins and the loss of crystallinity of the materials. Hydroxypropyl-β-cyclodextrin:TiF₄ 72 h resulted in lower %SML than negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, and TiF₄ (p < 0.05). NaF differed from all groups (p < 0.05), except for hydroxypropyl-β-cyclodextrin:TiF₄ 72 h (p = 0.83). ΔZ of hydroxypropyl-β-cyclodextrin:TiF₄ 72 h was higher than negative control, hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, γ-cyclodextrin:TiF₄ 1 2 h, γ-cyclodextrin:TiF₄ 72 h, and NaF (p < 0.05) and similar to TiF₄ and hydroxypropyl-β-cyclodextrin:TiF₄ 12 h (p > 0.05). SEM/EDS detected Ti in the blocks subjected to TiF₄-products.

CONCLUSION

The hydroxypropyl-β-cyclodextrin:TiF₄ 72 h solution showed caries preventive effect on the surface and subsurface of the enamel.

CLINICAL RELEVANCE

A hydroxypropyl-β-cyclodextrin nanosystem, in association with TiF₄ after 72 h of complexation, may be a promising agent for the prevention of enamel demineralization.

Cyclodextrin and TiF4 Nanocomplex on Enamel Demineralization

The aim of this study was to assess the effect of a newly developed nanocomplex formed of hydroxypropyl-b-cyclodextrin and 1% titanium tetrafluoride (TiF4) after distinct complexation periods (12/72 h) on demineralization of bovine enamel in vitro. Enamel blocks (n=60) were allocated in different groups: Mili-Q water, hydroxypropyl-b-cyclodextrin, 1% TiF4, hydroxypropyl-b-cyclodextrin + 1% TiF4 after 12 h of complexation and hydroxypropyl-b-cyclodextrin + 1% TiF4 after 72 h of complexation. The samples were evaluated by surface microhardness, cross-sectional microhardness and micro-CT. Scanning electron microscopy and energy dispersive X-ray spectrometry (SEM/EDX) were also obtained. Hydroxypropyl-b-cyclodextrin + 1% TiF4 after 12 h complexation resulted in lower percentage of surface microhardness loss compared to Mili-Q water, hydroxypropyl-b-cyclodextrin, 1% TiF4 and hydroxypropyl-b-cyclodextrin + 1% TiF4 after 72 h of complexation group, with a large effect size (from 1.307 to 2.943) and high power (84.9 to 99%). All groups resulted in similar integrated mineral loss (ΔZ) obtained by both internal microhardness and micro-CT techniques. Enamel treated with TiF4 and TiF4 + hydroxypropyl-b-cyclodextrin groups showed a TiO2 glaze-layer, while EDX evaluation identified Ti. The solution containing the inclusion complex of hydroxypropyl-b-cyclodextrin + TiF4 with 12 h of complexation period demonstrated a significant ability to reduce surface demineralization of sound enamel under an artificial cariogenic challenge.

The Effect of Titanium Tetrafluoride Treatment and the CO2 Laser on Acid Resistance of Human Enamel

Introduction: Titanium tetrafluoride (TiF4 ) is deemed more effective than the previous fluoride compounds. To enhance the effect of the fluoride compounds, researchers have suggested their association with lasers, although there are conflicting results in this area. We evaluated the acid resistance of enamel after treatment with the CO₂ laser and TiF4 . Methods: Thirteen human premolar teeth were sectioned into 5 parts and each segment was assigned to a study group: co (control): without treatment, AF: enamel treatment with APF 1.23% for 4 minutes, TF: enamel treatment with TiF4 4% for 1 minute, TF-L: enamel treatment with TiF4 4% and then the CO₂ laser (Peak power: 1 W, pulse duration: 10 ms, interval time: 500 ms, Beam spot size: 0.2 mm, distance: 2 cm), L-TF: enamel treatment with the CO₂ laser and then TiF4 4%. Each sample was kept for 7 days in acidic solution of hydroxyethyl cellulose at pH=4.5, and the amount of the calcium ion released in the solution was measured by atomic absorption spectrometry. Data were analyzed by ANOVA and Bonferroni tests. The significance level was set at 0.05. Results: The average concentration of the calcium ion released in acidic solution was 197.46, 153.30, 99.23, 61.23, 55.46 ppm in the groups respectively. There was a significant difference between the study groups (P<0.0001). Only the difference between TF-L and L-TF was not significant (P>0.05). Conclusion: The loss of calcium from the enamel samples in the groups treated with a combination of the laser and TiF4 was significantly lower than the groups treated with fluoride alone, or the control group. It did not make a significant difference whether the CO₂ laser was applied before or after TiF4 .

Mechanical Properties of Multifunctional TiF4 from First-Principles Calculations

Titanium tetrafluoride (TiF₄) plays a crucial role in prerestorative dentistry, the synthesis of metal fluorides and titanium silicate thin films, enhancing the photocatalytic activity of TiO₂, and hydrogen storage applications. Though TiF₄ is touted for superior catalytic activity in deflating the decomposition temperature of metal hydrides, its fundamental properties have not been studied yet. Compressibility is a vital parameter during mechanical milling and hydrogen cycling processes from solid metal hydrides to sustain its stability. Even though many high-pressure studies are available on metal hydrides, a similar study on the TiF₄ additive has not yet been conducted by either theoretical or experimental methods. In an effort to identify the compressibility of the TiF₄ catalyst, we have performed state-of-the-art density-functional-theory-based calculations for three chemical states of TiF_x (x = 4, 3, and 2). The mechanical strength of a material is derived from interatomic interactions, which in turn are influenced by the microstructure and bonding. The results highlight the superior structural, electronic, mechanical, and optical properties of orthorhombic TiF₄, which has octahedral columns similar to those of bone tissue material (hydroxyapatite). This article highlights the stable iono-covalent F-Ti-F bonding of the +4 state of titanium fluoride. Materials with Young's moduli close to that of bone (20-30 GPa) have been intensely searched for bone implants. TiF₄ can be used for this purpose because its average Young's modulus is 47 GPa. Our detailed analysis of charge density in TiF₄ sheds light on its unique bonding characteristics, which result in its extraordinary mechanical properties, making TiF₄ a multifunctional material not only for dental fillings but also for orthopedic and catalytic applications.

Cytotoxicity of novel fluoride solutions and their influence on mineral loss from enamel exposed to a Streptococcus mutans biofilm

OBJECTIVE

This study evaluated the cytotoxicity, antimicrobial activity and in vitro influence of new fluoridated nanocomplexes on dental demineralization.

DESIGN

The nanocomplexes hydroxypropyl-β-cyclodextrin with 1% titanium tetrafluoride (TiF₄) and γ-cyclodextrin with TiF₄ were compared to a positive control (TiF₄), a blank control (without treatment) and negative controls (hydroxypropyl-β-cyclodextrin, γ-cyclodextrin, deionized water), following 12- and 72-hour complexation periods. The cytotoxicity was assessed using the neutral red dye uptake assay at T1-15 min, T2-30 min and T3-24 h. A minimum bactericidal concentration (MBC) against Streptococcus mutans (ATCC 25175) was performed. Enamel blocks were exposed to an S. mutans biofilm, and the percentage of surface microhardness loss was obtained. Biocompatibility and microhardness data were analysed using ANOVA/Tukey tests (p < 0.05).

RESULTS

At T1, the cell viability results of the nanocomplexes were similar to that of the blank control. At T2 and T3, the 72 h nanocomplexes demonstrated cell viability results similar to that of the blank, while the 12 h solutions showed results different from that of the blank (p < 0.05). All fluoridated nanocompounds inhibited S. mutans (MBC = 0.25%), while the MBC of TiF₄ alone was 0.13%. All fluoridated compounds presented a percentage of surface microhardness loss lower than that of deionized water (p < 0.05).

CONCLUSIONS

The new fluoridated nanocomplexes did not induce critical cytotoxic effects during the experimental periods, whilst they did show bactericidal potential against S. mutans and inhibited enamel mineral loss.

Effect of the Inclusion Nanocomplex Formed of Titanium Tetrafluoride and β-Cyclodextrin on Enamel Remineralization

OBJECTIVE

Titanium tetrafluoride (TiF₄) is a topical agent used in the control of dental caries; however, it is highly acidic. To minimize this effect, cyclodextrins (CDs) are used. This study evaluated the in vitro potential of TiF₄ and β-CD on remineralization.

METHODS

Forty bovine enamel blocks were selected by microhardness and randomly assigned to four groups (n = 10 per group): control (distilled and deionized water), 1% β-CD solution, 1% TiF₄ solution, and TiF₄: β-CD solution. The blocks were subjected to a pH cycling regimen for 8 days. After that, samples were evaluated by cross-sectional microhardness (CSMH), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). Data were assessed for normality and analyzed using ANOVA and Tukey's tests (α = 0.05).

RESULTS

Regarding CSMH, TiF₄: β-CD was statistically superior to the control (P = 0.033), β-CD (P = 0.022), and TiF₄ (P = 0.006). SEM photomicrography revealed the titanium dioxide coating on slabs treated with TiF₄ and TiF₄: β-CD. EDS assessment demonstrated the presence of titanium on the surface of slabs treated with TiF₄ and TiF₄: β-CD.

CONCLUSION

The solution containing the inclusion nanocomplex formed of TiF₄ and β-CD was able to reharden the enamel subsurface.

Prevention of Enamel Adjacent to Bracket Demineralization Following Carbon Dioxide Laser Radiation and Titanium Tetra Fluoride Solution Treatment: An In Vitro Study

Introduction: The aim of this study was to assess the caries-preventive potential of carbon dioxide (CO₂) laser application in conjunction with the use of titanium tetra fluoride solution on the enamel adjacent to bracket. Methods: Seventy-five freshly extracted bovine incisors were used. In order to attach the brackets, the area of examination was covered with adhesive tape to limit acid etching of the entire enamel surface. Metal orthodontic brackets for upper central were bonded to all the teeth following the manufacturer's instruction. Then all the teeth were painted with 2 layers of acid-resistant nail varnish on all surfaces except the boxes area cervical to the brackets. The teeth were then randomly divided into five groups (n = 15): control group (C); laser group (L); titanium group (T); laser-titanium group (LT) and titanium-laser group (TL). The laser-titanium group was first irradiated with CO₂ laser (same as the L group) then TiF4 solution was applied on the enamel (same as the T group). Samples in the TL group were first treated with TiF4 solution (same as the T group) and then irradiated with CO₂ laser on the surface (same as the L group). Then, the teeth were immersed in pH-cycling solutions. After that, the amount of calcium released into the two solutions (de- and re-mineralization) was measured with an atomic absorption spectroscopy. The data were analyzed by one-way Analysis of var-iance (ANOVA) and Tukey test. Results: Calcium loss in LT, TL and T groups were significantly lower than those in the L and C groups (P < 0.05). Conclusion: The application of Titanium tetra fluoride 4% solution on enamel can inhibit as much as 87% of subsequent caries like lesion progression.

Comparison of enamel remineralization potential after application of titanium tetra fluoride and carbon dioxide laser

BACKGROUND AND AIMS

The aim was comparison of enamel remineralization after application of APF, TiF₄ and CO₂ laser alone or in combination.

MATERIALS AND METHODS

Enamel blocks were prepared from human third molars. The initial surface hardness was determined by Vicker's hardness tester. The samples underwent a demineralization regimen for 7 days to produce artificial initial caries. The hardness of enamel blocks with white spot lesions was measured, and the samples which had the mean hardness change of 65-90%, were selected, and randomly divided into 5 groups (N=15): G1: control; G2: APF 1.23%; G3: TiF₄ 4%; G4: TiF₄ 4% followed by CO₂ laser (10.6 µm wavelength, 1 W peak power, 10 ms pulse duration, 500 ms repeat time, 0.2 mm beam spot size, 2 cm distance); G5: CO₂ laser (same parameters) followed by TiF₄ 4%. Surface hardness recovery was measured after the treatments. Three samples in each group were observed under scanning electron microscope at ×1,000 magnification. Data were analyzed by repeated measure ANOVA and Bonferrouni tests. Significance level was set at 0.05.

RESULTS

G2, G3, G4 indicated significant differences with control and G5 (p<0.05). Surface hardness in G5 was not significantly different from control (p=0.7) in enamel hardness test. There was not a significant difference between G2 & G3, G2 & G4, and G3 & G4 (p=1). The SEM results indicated globules of calcium fluoride on the surface in G2, and a smooth glaze-like surface layer in G3 and G4. In G5, some micro-cracks without any glaze-like layer were observed.

CONCLUSIONS

APF, TiF₄ and TiF₄ before CO₂ laser irradiation significantly increased the micro-hardness of initially demineralized enamel surfaces. CO₂ laser irradiation before TiF₄ application could not remineralize the white-spot lesions.

Comparative evaluation of microhardness of dentin treated with 4% titanium tetrafluoride and 1.23% acidic phosphate fluoride gel before and after exposure to acidic pH: An ex vivo study

AIM

The aim of this study was to comparatively evaluate the effect of 4% titanium tetrafluoride (TiF4) and 1.23% acidic phosphate fluoride (APF) gel on the microhardness of human coronal dentin.

MATERIALS AND METHODS

Thirty noncarious extracted premolars were collected and sectioned buccolingually with the help of diamond disk. Exposing the sectioned surface, teeth were embedded in self-cure acrylic. Exposed coronal dentin was polished with abrasive papers starting with 220-5000 grit. Microhardness was evaluated by Vickers microhardness evaluator, at four different stages as follows - stage 1: Baseline values, Stage 2: Exposure of specimens to acidic environment at a pH 1 for 5 min, Stage 3: Application of 1.23% APF gel and 4% TiF4 (after dividing the specimens into two groups, i.e., Group A and B, respectively), and Stage 4: Followed by exposure of fluoridated specimens to acidic protocol as mentioned above.

RESULTS

Paired t-test was used to compare the readings between Groups A and B. Group B has shown greater resistance to decrease in microhardness of coronal dentin (P < 0.05) on exposure to acidic protocol.

CONCLUSION

Due to acidic pH (1.5) of 4% TiF4, amount of increase in microhardness of dentin is <1.23% APF gel. 4% TiF4 was more effective in resisting demineralization than 1.23% APF gel.

Novel tea polyphenol-modified calcium phosphate nanoparticle and its remineralization potential

Tea polyphenols (TP) are not only potent antimicrobial and antioxidant agents but also effective modifiers in the formation of nanosized crystals. Since nano-hydroxyapatite (n-HA) is known to enhance remineralization of dental hard tissue, our aims were to synthesize nanosized calcium phosphate particles incorporating TP and to test their potential as caries preventive agent. An ammonia water diffusion method was used to synthesize nanosized calcium phosphate particles (TP-CaP) in the presence of various amounts of TP. The resultant products were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The remineralization potential of the nano TP-CaP was then investigated in a 12-day pH-cycling model. Nano TP-CaP slurries, at pH 7.0 and pH 5.5, were applied onto preformed enamel lesions 4 × 3 min per day. n-HA slurries at pH 7.0 and pH 5.5 were used as positive controls, and deionized water was served as a negative control. SEM showed nanosized particles were only formed at 27 mg/mL of TP. Further characterization of the nanosized particles revealed the components were amorphous calcium phosphate, HA, and TP. Both surface microhardness and transverse microradiography analyses showed that nano TP-CaP at pH 5.5, but not at pH 7.0, significantly enhanced remineralization, to the same extent as the n-HA controls. Furthermore, significantly higher amount of TP was found in the supernatant of TP-CaP at pH 5.5 than those at pH 7.0. Since TP can inhibit bacterial growth and enzyme activities, the novel nanosized TP-CaP particle, at low pH, is a potential dual-functional-remineralization and antibacteria-product.

Efeito da aplicação tópica de um verniz de TiF4 quimicamente estável na desmineralização do esmalte dentário bovino: estudo in vitro

OBJETIVO: Avaliar, in vitro, o efeito preventivo da aplicação tópica de um verniz à base de tetrafluoreto de titânio quimicamente estável e de um verniz à base de fluoreto de sódio sobre o esmalte bovino, mediante ciclagem de pH. METODOLOGIA: A amostra foi constituída por 75 blocos de esmalte bovino 3×3 mm, sendo 15 aleatoriamente alocados em cada um dos cinco grupos: G1: Dentifrício Fluoretado + Verniz sem princípio ativo; G2: Dentifrício Fluoretado + Verniz à base de TiF4 (4 minutos); G3: Dentifrício Fluoretado + Verniz à base de TiF4 (24 horas); G4: Dentifrício Fluoretado + Verniz à base de NaF (24 horas); G5: Dentifrício Fluoretado. A ciclagem de pH foi realizada por um período de 14 dias, constando de oito ciclos, a 37 °C. Os blocos tratados foram mantidos em solução desmineralizante por oito horas e, por 16 horas, em solução remineralizante, sendo submetidos à análise da superfície em microscopia eletrônica de varredura e espectroscopia de energia dispersiva. RESULTADO: O verniz à base de TiF4 promoveu uma maior proteção ao esmalte quando comparado com os demais grupos. Mesmo após o período de ciclagem, foram encontrados fósforo, cálcio, sódio, magnésio, titânio, cloro, silício, alumínio, enxofre, potássio, oxigênio e flúor na superfície do esmalte. CONCLUSÃO: O aspecto da estrutura adamantina submetida à ação do tetrafluoreto de titânio revelou a presença de uma película protetora. O cálcio e o fósforo foram os principais compostos inorgânicos encontrados no esmalte, sendo observadas alterações na constituição química da camada superficial adamantina em função do tratamento com fluoreto instituído.

In vitro reduction of dental erosion by low-concentration TiF4 solutions

The aims of this study were to compare daily versus single applications of low-concentration TiF(4) solutions for reduction of enamel erosion and to evaluate the enamel surface loss due to application of these solutions. Sixty bovine enamel samples were randomly divided into 2 groups: single versus daily treatment with TiF(4) solution (ST vs. DT), which were subdivided into 5 subgroups (n = 6): 0% (control); 0.1, 0.5, 0.75 and 1% TiF(4) concentration. Fluoride treatment was performed by immersing specimens in 10 ml of the TiF(4) solutions for 5 min and rinsing them with tap water for 30 s. ST specimens were treated once only, DT specimens were treated before each erosion cycle. All specimens were subjected to 4 erosion cycles: 6 immersions of 2 min in Sprite, tap water rinse for 1 min and storage in artificial saliva for 1.5 h. Erosive enamel loss was measured using light profilometry, after each fluoride treatment and each erosive cycle. The values of surface loss/gain at application of the TiF(4) solutions did not significantly differ from zero. At the end of the 4 erosion cycles, 0.5% showed the least (ST: 3.45 ± 0.27 μm, DT: 1.08 ± 1.69 μm) and 1% showed the most surface loss (ST: 4.87 ± 1.13 μm, DT: 6.56 ± 1.49 μm). A significant reduction of surface loss was found only for 0.5% DT (p = 0.009). Within the limitations of an in vitro study, it was concluded that multiple applications of a 0.5% TiF(4) solution significantly reduced enamel erosion in vitro and caused no enamel loss at application.

Protection of short-time enamel erosion by different tetrafluoride compounds

OBJECTIVE

This in vitro study aimed to analyse the protective effect of differently concentrated titanium (TiF(4)), zirconium (ZrF(4)) and hafnium (HfF(4)) tetrafluoride on enamel erosion.

METHODS

Polished enamel surfaces of 36 bovine crowns were covered with tape leaving 4 enamel windows each 3mm in diameter exposed. The crowns were randomly assigned to six groups (each n=6) and pretreated with 4% TiF(4), 10% TiF(4), 4% ZrF(4), 10% ZrF(4), 4% HfF(4) or 10% HfF(4) for 4 min (first window), 10 min (second window) or 15 min (third window). The fourth window of each crown was not pretreated and served as control. Erosion was performed stepwise with 1% HCl (pH 2) in five consecutive intervals of each 15 s (total 75 s). Enamel dissolution was quantified by colorimetric determination of phosphate release into the acid. For each tooth, cumulative phosphate loss of enamel pretreated with one of the tetrafluoride compounds was calculated as percentage of the respective control and statistically analysed using two-way ANOVA.

RESULTS

Enamel erosion was significantly reduced by TiF(4), ZrF(4) and HfF(4) application. Cumulative phosphate loss (mean % of control, 75s erosion) after 4-15 min application was significantly lower for 4% ZrF(4) (7-11%), 10% ZrF(4) (2-6%), 4% HfF(4) (11-9%) and 10% HfF(4) (12-16%) compared to 4% TiF(4) (42-27%) and 10% TiF(4) (54-33%). Only for 4% and 10% TiF(4), phosphate loss decreased with increasing duration of application, but also increased with increasing acid intervals.

CONCLUSION

TiF(4), ZrF(4) and HfF(4) might protect enamel against short-time erosion, but protection was more enhanced by ZrF(4) and HfF(4) compared to TiF(4) application overtime.